ANARTHROPODA. 129 
The entire sub-kingdom of the Axznzlosa is divided into two 
great divisions termed Arthropoda and Anarthropoda, accord- 
ing as the body is provided with jointed appendages or not. 
In the Arthropoda, in which the body-rings are furnished (some 
or all) with jointed appendages, are included the Crustaceans 
(lobsters, crabs, &c.), the spiders and scorpions, the centipedes, 
and the insects, In the Axzarthropoda, in which there are no 
true jointed appendages, are included the spoon-worms, leeches, 
earth-worms, tube-worms, and sand-worms.* 
Division I. ANARTHROPODA.—In this division of the Axzxz- 
losa, the locomotive appendages are never distinctly jointed or 
articulated to the body. mn this division are included two 
principal classes—the Gephyrea and the Aunelida.t 
Cuiass I. GEPHYREA.—This class is a very small one, and 
includes a number of worm-like animals, which in most respects 
are very similar to the following class of the Azmelida, but are 
distinguished by having no locomotive appendages attached to 
the sides of the body. They were long placed amongst the 
Fig. 57.—Gephyrea. Syrinx nudus (after Forbes). 
Echinodermata, having a decided relationship to the worm-like 
Hlolothurians. They are distinguished, however, by never 
secreting calcareous matter in the skin, and by haying no water- 
vascular or ambulacral system. There can be no doubt, how- 
ever, that the Gephyrea are, on the whole, very nearly related 
* The Anarthropfoda are often united with the Scolecida into a common sub-king- 
dom under the name of Verses; in which case the Echinodermata are retained 
apart in a special sub-kingdom. 
+ A third class has been constituted under the name of Chefognatha for some 
singular marine animals, transparent and worm-like in form, with lateral fins at the 
hinder end of the body, and having the mouth armed with bristles. They form the 
genus Sagztia. 
